Processed cheese, widely available in sliced and loaf forms, has become one of the most popular selling cheese products. Processed cheese products are particularly popular with children. Therefore, opportunities to increase the nutritional values and/or health benefits of processed cheese products without significantly impacting the organoleptic properties of the resulting product would be highly desirable.
Process cheese is conventionally prepared by grinding, and/or mixing while heating, one or more varieties of milk fat-containing natural cheeses, such as, for example, Cheddar cheese, Colby cheese, Swiss cheese, Brick cheese, Muenster cheese, Pasta Filata cheese, washed curd, and granular curd cheese. The resulting cheese is then blended with other dairy products, such as non-fat dry milk and whey solids, and emulsifying salts, such as disodium phosphate, at temperatures which are sufficiently elevated to pasteurize the cheese, to produce a homogeneous, pumpable, fluid cheese material that may be formed into sheets, slices, or other desired forms.
There are three general types of process cheese: pasteurized process cheese, pasteurized process cheese food, and pasteurized process cheese spread. These process cheeses have certain characteristics that are desirable to cheese consumers. They all have a smooth, creamy texture and a slight firmness that is attributable to the presence of at least 20 percent fat in the process cheese formulation. Based on the Standards of Identity, the main differences between the three types of process cheese are their moisture and fat content, and the use of optional ingredients in their manufacture. These cheeses typically are made in large quantities using a horizontal cooker (sometimes called a laydown cooker). Often, the process cheese is then automatically packaged in airtight cartons.
The health benefits of soybeans have been known for some time. For centuries, soybeans have been the primary source of protein in Asian countries, and in recent years the popularity of soy-based products has increased in the United States. Along with a tendency to lower cholesterol levels, soybeans have recently been linked with, or suggested as having a possible role in, inhibiting cancerous or tumor cells. Additionally, soy protein contains an amino acid profile that is among the most complete of all vegetable protein sources, and resembles, with the exception of the sulfur-containing amino acids, the pattern derived from high-quality animal protein sources. Thus, efforts have been made to incorporate soy into a wide variety of foods.
It would therefore be desirable to provide a process cheese type product containing, significant levels of soy protein while maintaining with the flavor, texture and melt characteristics of processed cheese.
U.S. Pat. No. 3,982,025 (Sep. 21, 1976) provides a method for the production of a spreadable soy cheese product. An aged soy cheese (prepared by fermenting soy milk with a lactic acid cheese starter culture) is mixed with an edible oil (about 45 to about 60 weight percent based on the weight of dry solids in the soy cheese), emulsifying salts, and water under high shear and high temperature conditions. The resulting spread contains about 11 weight percent soy protein.
U.S. Pat. No. 4,080,477 (Mar. 21, 1978) relates to the production of a processed cheese-like product containing soy cheese. A casein-containing material (e.g., caseinates, dairy cheese, dairy cheese curd, whole milk solids, skim milk solids, and mixtures thereof) and an emulsifying salt are added to soy cheese curd under relatively high shear conditions while heating to about 50-85° C. Generally, the casein-containing material is present in an amount sufficient to provide at least one part by weight casein per 100 parts by weight soy cheese and preferably about one to ten parts by weight casein per 100 parts by weight soy cheese.
U.S. Pat. No. 4,303,691 (Dec. 1, 1981) provides a proteinaceous food product simulating cheese comprising a blend of soy protein (e.g., soy isolate, cold insoluble soy fraction, or mixtures thereof), gelatin, hydrocolloid gum, fat, and water.
U.S. Pat. No. 4,349,576 (Sep. 14, 1982) provides a method for producing soy isolates. The soy isolates can be used to replace about 20-60 percent caseinate in a meltable imitation cheese.
U.S. Pat. No. 4,678,676 (Jul. 7, 1987) provides a method of producing a cheese-like emulsified food by blending tofu, an oil or fat, a heat coagulable protein (e.g., whey protein concentrate), and a stabilizer and then heating the blend to gel the protein component.
U.S. Pat. No. 5,858,449 (Jan. 12, 1999) provides an isoflavone-enriched soy protein product which can be incorporated into, for example, imitation processed cheese spreads. Such spreads were produced by first preparing a dry blend of rennet casein, soy protein product, and whey. Separately, a blend of oil, water, and emulsifying salts were mixed in a processed cheese cooker. The dry blend and lactic acid were added slowly to the mixture in the cheese cooker, and the resulting mixture was heated to produce a soy-based imitation processed cheese spread.
Although these methods generally provide soy in a cheese-like product, it is still desirable to provide significant levels of soy protein in a product which more closely mimics the flavor and textural attributes of typical dairy-based processed cheese products. The present invention provides organoleptically pleasing processed cheese products having significant levels of soy protein.